Electric rotary switch with improved stamped contact means

ABSTRACT

An electric switch having a plurality of individual spaced contacts and a common contact lying in the same plane and supported by a stationary contact carrier of insulating material. Certain of the individual spaced contacts and at least a portion of the common contact have edge portions equally spaced from an elongated surface of the stationary contact carrier. Depending upon the switching requirements, the individual spaced contacts and the common contact can be provided with integral terminal means for connecting the contacts into an electrical circuit or some of the individual spaced contacts can be provided with integral stamped inductance means. A movable contact carrier of insulating material is movable along the elongated surface of the stationary contact carrier and a bridging contactor constrained to move with the movable contact carrier selectively connects or shorts certain individual spaced contacts. The bridging contactor for the electric switch is blanked from sheet material with a plurality of contact portions and stored for future use. Depending upon the application of the switch, the extra contact portions are severed from the contactor which is then curved and ready for assembly to produce the electric switch.

United States Patent 72] Inventors Thomas R. Beaver,

Ellthart, Ind.; Kenneth C. Allison, Crystal Lake, Ill. [21] Appl. No. 843,864 [22] Filed Mar. 10, 1969 [45] Patented Mar. 23, 1971 [73] Assignee CTS Corporation,

Elkhart, Ind.

[54] ELECTRIC ROTARY SWITCH WITH IMPROVED STAMPED CONTACT MEANS 13 Claims, 9 Drawing Figs.

[52]- U.S. Cl. 200/11, 200/ l 66 [51] Int. Cl ..H0lh 19/58 [50] Field'otSearch ZOO/110, 166 (CTS); 336/20 [56] References Cited UNITED STATES PATENTS 3,219,785 11/1965 Allison 200/11(D) 3,242,271 3/1966 Stephan et al. 200/11(D) 3,254,164 5/1966 Lewandowski 200/1 1(D) 3,316,363 4/1967 Valdettaro et al. 200/1 1(D) Primary Examiner- -Robert K. Schaefer Assistant Examiner-LR. Scott Attorneys-John .l. Gaydos and Ralph E. Krisher ABSTRACT: An electric switch having a plurality of individual spaced contacts and a common contact lying in the same plane and supported by a stationary contact carrier of insulating material. Certain of the individual spaced contacts and at least a portion of the common contact haveiedge portions equally spaced from an elongated surface of the stationary contact carrier. Depending upon the switching requirements, the individual spaced contacts and the common contact can be provided with integral terminal means for connecting the contacts into an electrical circuit or some of the individual spaced contacts can be provided with integral stamped inductance means. A movable contact carrier of insulating material is movable along the elongated surface of the stationary contact carrier and a bridging contactor constrained to move with the movable contact carrier selectively connects or shorts certain individual spaced contacts. The bridging contactor for the electric switch is blanked from sheet material with a plurality of contact portions and stored for future use. Depending upon the application of the switch, the extra contact portions are severed from the contactor which is then curved and ready for assembly to produce the electric switch.

PATENTED MAR23 I97! SHEEI 2 0F 2 E R U B F FIGURE- 6 INVENTORS KENNETH C. ALLISON THO AS R. BEAVER lELlEC'lllitlC ROTARY SWITCH WITH llMlPlRGl/ED STAMPEID CONTACT MEAN The present invention relates generally to an electric switch and, more particularly, to an electric switch having a plurality of individual spaced contacts sequentially engaged by a movable bridging contactor and to a method of making the same.

With the increasing complexity of electronic equipment, more complex switching functions are being performed. A few years ago improved electric switches such as shown in Allison U.S. Pat. Nos. 2,988,606 and 3,219,785 assigned to the same assignee as the present invention, were capable of performing the complex switching functions then required of electronic equipment. In order to perform the present day complex switching functions with existing switches, it is necessary to combine several switch sections and/or to use clusters of bridging contactors with each of the sections causing an increase in the manufacturing cost of the switch. It would, therefore, be desirable to provide an improved electrical switch for performing a complex variety of switching functions and im proved supporting means extending radially of a switch stator.

In certain electronic equipment it is preferable to change the inductance in a circuit according to a predetermined sequence. Inductance members can be electrically connected with lead wires to the terminals of an electrical switch or integrally stamped with the contacts as shown in U.S. Pat. No. 3,370,259. Generally any connection made in securing a terminal of a switch increases the manufacturing cost of the electronic equipment especially if such electrical connections are made manually. It would, therefore, also be desirable to provide an improved electric switch having a plurality of inductance members integral with certain preselected contacts and embedded in a molder stator.

Accordingly, it is an object of the present invention to provide an improved electric switch. Another of object of the present invention is to provide an improved electric switch having a plurality of individual spaced contacts and a common contact embedded in a stationary contact carrier having radially extending support arms. An additional object of the present invention is to provide an electric switch for sequentially connecting a plurality of individual spaced contacts to other selected individual spaced contacts or shorting a group of selected individual spaced contacts without engaging a common contact. A further object of the present invention is to provide an improved electric switch having stamped inductance members integral with certain of the individual spaced contacts and embedded in a molded stator. A still further object of the present invention is to provide a method of making an electric switch with a bridging contactor having certain contact portions that are severed prior to assembly of the bridging contactor with the movable contact carrier of the switch for performing a specific switching function. Further objects and advantages of the present invention will become apparent as the following description proceeds, and the features of novelty characterizing the invention will be pointed out withparticularity in the claims annexed to and forming a part of this se specification.

Briefly, the present invention comprises a plurality of individual spaced contacts and a common contact lying in the same plane and fixed to a stationary contact carrier with the edge portions of certain preselected individual spaced contacts and of a portion of the common contact equally spaced from an elongated surface of the carrier. A pair of radially extending support arms are integral with the contact carrier and terminals are embedded in one of the support arms. In another embodiment, certain of the individual spaced contacts are fixed to the carrier and extend a different predetermined distance from the elongated surface. Depending upon the switching requirements, certain of the individual spaced contacts are provided with terminals for securing components or lead wires thereto or are provided with integral stamped inductance members. A movable contact carrier supporting a bridging contactor selectively connects the individual spaced contacts with the common contact or with other individual spaced contacts or shorts certain individual spaced contacts as the movable contact carrier is actuated from one position to another.

For a better understanding of the present invention, reference may be had to the accompanying drawings wherein the same reference numerals are applied to like parts and wherein:

FIG. I is an isometric view of an electric switch having terminals and stamped inductance members integral with the individual spaced contacts embedded in a molded stator;

FIG. 2 is a fragmentary sectional view taken along line II-II of FIG. 1;

FIG. 3 is a fragmentary sectional view taken along lines III-Ill of FIG. 1;

FIG. 4 is an exploded view of the electric switch shown in FIG. 1;

FIG. 5 is a fragmentary top plan view of the switch stator shown in FIG. 4;

FIG. 6 is a top plan view of a blanked bridging contactor before any of the individual contact portions have been severed therefrom;

FIG. 7 is a side view of a bridging contactor with certain of the contact portions removed and wherein the base portion of the bridging contactor has been curved;

FIG. 8 is another embodiment of a stator of the electric switch shown in FIG. 1 wherein terminals are integral with all of the individual spaced contacts and the common contact; and

FIG. 9 is a side view of the switch shown in FIG. 8.

Referring now to FIGS. 1 through 5 of the drawings, there is illustrated an electric switch of the type employed in electric equipment such as television receivers, aircraft transmitters and receivers, and two-way radios generally indicated at 10, comprising a switch stator 11 and a switch rotor 12 rotatably mounted within the switch stator 11.

Considering first the switch stator II, it comprises an annular contact carrier 13 molded of suitable electrical insulating material having embedded therein a plurality of radially disposed individual spaced contact fingers 14. The contact carrier 13 is defined by a top surface 13a, a bottom surface i312 parallel to the top surface and by elongated inner and outer surfaces and 13d transverse to the top and bottom surfaces. The contact fingers 14 are provided with individual spaced contacts Ma and 14b (see FIG. 4) arranged in a row along the elongated inner surface I30 of the contact carrier 13. Extending radially outwardly from the contact carrier 13 are a pair of support or mounting arms 15 and I6 having reduced end portions 15a and 16a' insertable into not-shown channels provided in a housing forming a part of the electrical equipment.

The switch stator ll of the present invention is produced by forming groups or clusters of perforations in a strip of sheet metal for spacing partly defined contact fingers, molding the contact carrier 13 above and below the partly defined contact fingers of each group of perforations, and then blanking the remaining portions of the contact fingers from the strip of sheet metal to produce the switch stator lll. Reference should be made to Allison U.S. Pat. Nos. 2,988,696 and 3,219,785 for a more thorough description of the manufacturing process employed in making the present type of switch stators.

A common contact 17 also is supported by the contact carrier l3 and supporting means ll7a integral with the common contact 17 are embedded in the contact carrier I3 for fixedly securing the common contact 17 to the contact carrier. Preferably the individual spaced contacts Ma and 14b and the common contact 17 are coplanar, i.e., lie in the same plane. Depending upon the application of the switch, the individual spaced contacts are long and short contacts 14a and Mb, as best shown in FIG. 4 of the drawings. Both the long and short individual spaced contacts are coplanar with the common contact. For convenience, the long and short individual spaced contacts will hereinafter be referred to as long contacts 14a and short contacts 14b.

When the electric switch is employed for altering the inductance of a circuit, certain of the contact fingers 14 comprises a long or short contact 14a or 1 1b, an embedded portion 140 (see FIGS. 2 and 3) and a stamped inductance member 18 extending radially outwardly from the contact carrier 13. Terminals 19 are integral with the contact fingers not provided with stamped inductance members 18. The stamped inductance members 18 provide adequate inductance values above 100 MHZ. To increase the inductance of the inductance members 18, an elongated slot 18a is provided in each of the induc ance members 18, the length of the slot varying with the inductance desired. In the embodiment shown in FIGS. 1 to 5, all of the inductance members 18 are connected to each other with U-shaped connecting members 20 (see FIG. 5), the ends 20a of the legs of each of the U-shaped connecting member 20 being connected to each of the distal ends 18b of the inductance members 18. Fine adjustment between adjacent inductance members 18 is obtained by bending the fan or inner section 2012 of each of the connecting portions 20 out of the plane defined by the inductance members 18. The length of the slot 20c also varies with the inductance desired. Notshown inductance coils can be connected between adjacent terminals 19 when it is desired to obtain inductance values below 100 MHZ. One of the inductance members 180 and a terminal 140 are at least partially embedded in the radially extending support arm 16. As the switch rotor 12 is rotated from one position to another to connect electrically one of the long or short contacts 14a or 14b to the common stationary contact, the inductance in the circuit is increased or decreased.

For the purpose of electrically connecting the long contacts to the short contacts or to the common contact, a bridging contactor 21 provided with long and short contact 21a and 21b is constrained to rotate with the switch rotor or movable contact carrier 12. The rotor 12 is preferably actuated with a notshown shaft received in an aperture 12a provided in the center of the rotor, the angular position of the shaft being determined by a not-shown indexing mechanism well known in the art. As shown in the drawings, the switch rotor 12 comprises a pair of circular sections 22, having a diameter slightly smaller than the inside diameter of the contact carrier 13. Each of the circular sections 22 is identical to keep to a minimum the number of different parts necessary for making the switch 10. Each of the circular sections 22 comprises an outer rim portion 22a and an inner hub portion 2212 provided with the aperture 12a for receiving a shaft. As best shown in FIGS. 3 and 4, a peripheral lip 22c depending from the rim portion slidably engages the contacts 14a and 14b as the switch rotor 12 is actuated and limits axial movement of the rotor 12 relative to the stator 11. Radially spaced runners 22d extend from the hub portion 22b to the peripheral lip 22c and define cavities 23 for receiving the contact portions 21a and 21b of the bridging contactor. The bridging contactor 21 is also provided with a plurality of laterally spaced tabs 21c connected together with a base portion 27 receivable respectively in arcuate slots 24 and a groove 24a provided in the circular sections 22 for constraining the bridging contactor 21 to rotate with the switch rotor 12.

When the circular sections 22 are assembled to the contact carrier 13, the rim portions 22a of the pair of circular sections have their outer surfaces spaced apart a distance substantially equal to the thickness of the contact carrier (see FIGS. 2 and 3) while the hub portions 22b are of a slightly larger lateral dimension for receiving a shaft. The circular sections of the rotor are held together with a plurality of longitudinal pins 25 extending from each circular section and receivable in holes 26 provided in the other circular section. After a pair of circular sections are assembled with the tabs 210 of the bridging contactors received in the arcuate slots 24 the ends of the pins 25 projecting through the holes 26 are enlarged in a suitable manner to a maintain the circular sections in assembled relationship with the switch stator 11. Preferably one bridging contactor 21 is employed with each of the circular sections 22 of the movable contact carrier for balancing contact pressures and keeping contact resistance to a minimum. The switch stator 11 is usually fixedly secured to suitable not shown mounting means provided in electronic equipment and the switch rotor 12 is rotated through a predetermined angle to alter the relationship of the bridging contractor 21 relative to the contacts.

An important feature of the present invention is the method of making the bridging contactor. As best shown in FIG. 6 of the drawings, the bridging contactor after being blanked from sheet material, provided with a pair of long contact portions 210 and a plurality of short contact portions 21b. Depending upon the switching function required, all of the contact portions can be long or short or any combination thereof. More specifically, the bridging contactor comprises an elongated base portion 27 with the long and short contact portions 21a and 21b extending laterally in the same direction from the base portion 27. The plurality of tabs 21c extend laterally from the base portion in a direction opposite to the contact portions and are receivable in the arcuate slots 24 provided in each of the circular sections 22 of the rotor for constraining the bridging contractor 21 to rotate with the circular sections. Before the bridging contactor shown in FIG. 6 of the drawings is assembled to one of the circular sections 22, certain of the short contact portions usually are severed from the base portion. The bridging contactor 21 employed with the electric switch shown in FIG. 7 of the drawings employs a pair of long contact portions 21a and a single short contact portion 21b adjacent to one of the long contact portions 21a. The long contact portions of the bridging contactor shown in FIG. 7 always engage the short or long contacts 14a, 14b while the short contact portions engage only the common contact 17 or the long contacts 14a. The contact portions 21a have a predetermined transverse dimension d and, since the edge portions of the common contact 17 and the long stationary contacts 14a lie in an imaginary circle having a radius R, it is necessary that the longitudinal axis of the short contact portions 21b be spaced from each other at least twice said predetermined dimension. If the common contact 17 is removed from the switch stator, then the long contact portion 21a should be spaced approximately apart from the short contact portion 21b in order that the bridging contactor can sequentially connect the long contacts to the short contacts.

By making the bridging contactor in accord with the present invention, only one type of bridging contactor 21 instead of several need be blanked from sheet metal and stocked. After the specific configuration of the bridging contactor 21 is determined from a customer application, that is, the number and location of the short and long contact portions, the extra contact portions are severed from the base portion 27 and the remaining contact portions are formed normal to the base portion and dished as shown in FIGS. 2 and 4 of the drawings. The contact portions can also be dished when the bridging contactor is being blanked form sheet metal. In the last manufacturing step, the base portion of the bridging contactor 21 is curved to facilitate insertion of the tabs 21c into the arcuate slots 24 provided in the circular section of the rotor.

In the switch stator 111 shown in FIGS. 8 and 9 of the drawings, the arrangement of the long and short contacts and the common contact is identical to that shown in the embodiment shown in FIGS. 1 through 4 of the drawings. The only difference between the two switch stators is that the stator 111 shown in FIGS. 8 and 9 of the drawings has terminals 119 integral with all of the contacts 114a and l14instead of having stamped inductance means integral with some of the contacts. Also the stator 111 is provided with a pair of apertures for receiving of securing rods.

The electric switch of the present invention can, therefore, be provided with stamped inductance members 18 for altering the inductance of the circuit or with terminals 19 or 119 for connecting each of the contacts into an electric circuit.

Preferably and in accord with the present invention, the long contacts Maor 114a and the common contact 17 or 117 are provided with edge portions lying in an imaginary circle having a radio radius R while the short contacts 14b or ll4b have edge portions lying in an imaginary circle spaced a distance R, which is greater than R. Preferably the short contacts are spanned by the common contact as best shown in F168. 4 and 8. By having the edge portions of the long contacts and the common contact spaced the same predetermined distance from the elongated surface 13c of the contact carrier 13, selectively spaced short contact portions on the bridging contactor can connect predetermined long contacts to the common contact.

While there has been illustrated and described what is at present considered to be a preferred embodiment of the present invention and an additional modification thereof and a method of making the bridging contactor thereof, it will be appreciated that numerous changes and modifications are likely to occur to those skilled in the art and it is intended in the appended claims to cover all those changes and modifications which fall with within the true spirit and scope of the present invention.

We claim:

ll. An electric switch comprising a stationary contact carrier of insulating material having an elongated surface transverse to and lying between two parallel planes, a plurality of individual spaced stationary contacts fixed to the stationary contact carrier and projecting from said surface thereof, said individual spaced stationary contacts being arranged in a row along said surface and lying in a common plane intersecting said surface, each of said individual spaced stationary contacts having an edge portion spaced a predetermined distance from the elongated surface, a common stationary contact, supporting means integral with the common stationary contact and fixed to said stationary contact carrier mounting the common stationary contact in a position extending along said surface of the carrier, the common stationary contact having an edge portion spaced said predetermined distance from the elongated surface, a movable contact carrier of insulating material in front of and movable along said surface of the stationary contact carrier, and a bridging contactor carried by the movable contact carrier, said bridging contactor having first and second contact portions connected together the first contact portion moving in a path having circuit making engagement with said common stationary contact and the second contact portion moving in a path selectively engaging the individual spaced stationary contacts as the movable contact carrier is actuated to selectively electrically connect the individual spaced stationary contacts with the common stationary contact.

2. The electric switch of claim 1, wherein the contact carrier is annular, the plurality of individual spaced stationary contacts project from a portion of the elongated surface of the an nular contact carrier, and the common stationary contact spans a portion of the elongated surface.

3. The electric switch of claim 2, wherein certain of the individual spaced stationary contacts have edge portions spaced less than the predetermined distance from the elongated surface.

4. The switch of claim 2, wherein a plurality of individual spaced contacts are fixed to the contact carrier and disposed between the common contact and the elongated surface.

5. In a rotary multiposition electric switch, the combination of a stator comprising an annular member of insulating materia1 having elongated inner and outer edges, a plurality of individual contacts fixed to said annular member and having edge portions projecting in an are from the inner edge thereof, all of said individual contacts being fiat and coplanar, a flat arcuate common contact having an edge portion projecting in an arc, the are formed by the edge portions of the individual contacts and the are formed by the edge portion of the common contact defining an imaginary circle having a radius R, and a supporting arm for the common contact integral therewith and fixed to said annular member, said supporting arm being flat and coplanar with the individual contacts and holding the common contact coplanar with the individual contacts in edgewise spaced relation, terminals integral with the contacts, a radially extending support arm integral with the annular member, at least a portion of the terminal being embedded in the support arm, and a rotor comprising a bridging contactor for electrically interconnecting the contacts.

6. The switch of claim 5, wherein the plurality of stationary contacts are fixed to the annular member, all of the stationary contacts being flat and coplanar with the individual contacts, each of the stationary contacts having an edge portion projecting in an are having a radius greater than R and projecting from the inner edge, at least some of the stationary contacts being spanned by the common contact.

7. The switch of claim 5, wherein the bridging contactor comprises first and second contact portions connected together, the first contact portion moving in a path having a circuit-making engagement with the common contact and the second contact portion moving in a path selectively engaging the individual contacts as the rotor is actuated to selectively connect the individual contacts with the common contact, the first and second contact portions being connected together by an arcuate section.

8. The switch of claim 5, wherein the annular member is a molding, a plurality of contact fingers are embedded in the annular member between the inner and outer edges thereof, and the individual contacts extend from the contact fingers.

9. The switch of claim 8, wherein the first stamped inductance members are integral with a least a plurality of the contact fingers and project from the outer edge of the annular member, said inductance members being provided with a slot.

10. The switch of claim 9, comprising a plurality of second stamped inductance members connecting the first stamped inductance members in series, each of the second stamped inductance members being provided with a slot and comprising a fan for altering the inductance thereof.

11. In an electric switch, the combination of a first contact carrier of insulating material, a plurality of individual contacts fixed to the first contact carrier and projecting from a surface thereof, a common contact, supporting means integral with the common contact and fixed to said carrier mounting the common contact in spaced relationship to the individual contacts, a second contact carrier of insulating material in front of and movable relative to said surface of the first contact carrier, said bridging contactor comprising a first and second contact engaging portions, a base portion connecting the contact engaging portions together, one of the contact engaging portions having a predetermined transverse dimension, the longitudinal axis of the one contact engaging portion being spaced from the longitudinal axis of the other contact engaging portion at least twice predetermined dimension, the first contact engaging portion moving in a path having circuit making engagement with said common contact and the second contact engaging portion moving a in a path selectively engaging the individual contacts as the second contact carrier is actuated relative to the first contact carrier to selectively electrically connect the individual contacts with the common contact.

12. The switch of claim 11, wherein the base portion connecting the contact engaging portions together spans a distance equal to the distance spanned by the plurality of individual contacts.

13. The switch of claim 12, wherein the individual contacts and the common contact are spaced the same distance from the surface of the first contact carrier. 

1. An electric switch comprising a stationary contact carrier of insulating material having an elongated surface transverse to and lying between two parallel planes, a plurality of individual spaced stationary contacts fixed to the stationary contact carrier and projecting from said surface thereof, said individual spaced stationary contacts being arranged in a row along said surface and lying in a common plane intersecting said surface, each of said individual spaced stationary contacts having an edge portion spaced a predetermined distance from the elongated surface, a common stationary contact, supporting means integral with the common stationary contact and fixed to said stationary contact carrier mounting the common stationary contact in a position extending along said surface of the carrier, the common stationary contact having an edge portion spaced said predetermined distance from the elongated surface, a movable contact carrier of insulating material in front of and movable along said surface of the stationary contact carrier, and a bridging contactor carried by the movable contact carrier, said bridging contactor having first and second contact portions connected together the first contact portion moving in a path having circuit making engagement with said common stationary contact and the second contact portion moving in a path selectively engaging the individual spaced stationary contacts as the movable contact carrier is actuated to selectively electrically connect the individual spaced stationary contacts with the common stationary contact.
 2. The electric switch of claim 1, wherein the contact carrier is annular, the plurality of individual spaced stationary contacts project from a portion of the elongated surface of the annular contact carrier, and the common stationary contact spans a portion of the elongated surface.
 3. The electric switch of claim 2, wherein certain of the individual spaced stationary contacts have edge portions spaced less than the predetermined distance from the elongated surface.
 4. The switch of claim 2, wherein a plurality of individual spaced contacts are fixed to the contact carrier and disposed between the common contact and the elongated surface.
 5. In a rotary multiposition electric switch, the combination of a stator comprising an annular member of insulating material having elongated inner and outer edges, a plurality of individual contacts fixed to said annular member and having edge portions projecting in an arc from the inner edge thereof, all of said individual contacts being flat and coplanar, a flat arcuate common contact having an edge portion projecting in an arc, the arc formed by the edge portions of the individual contacts and the arc formed by the edge portion of the common contact defining an imaginary circle having a radius R, and a supporting arm for the common contact integral therewith and fixed to said annular member, said supporting arm being flat and coplanar with the individual contacts and holding the common contact coplanar with the individual contacts in edgewise spaced relation, terminals integral with the contacts, a radially extending support arm integral with the annular member, at least a portion of the terminal being embedded in the support arm, and a rotor comprising a bridging contactor for electrically interconnecting the contacts.
 6. The switch of claim 5, wherein the plurality of stationary contacts are fixed to the annular member, all of the stationary contacts being flat and coplanar with the individual contacts, each of the stationary contacts having an edge portion projecting in an arc having a radius greater than R and projecting from the inner Edge, at least some of the stationary contacts being spanned by the common contact.
 7. The switch of claim 5, wherein the bridging contactor comprises first and second contact portions connected together, the first contact portion moving in a path having a circuit-making engagement with the common contact and the second contact portion moving in a path selectively engaging the individual contacts as the rotor is actuated to selectively connect the individual contacts with the common contact, the first and second contact portions being connected together by an arcuate section.
 8. The switch of claim 5, wherein the annular member is a molding, a plurality of contact fingers are embedded in the annular member between the inner and outer edges thereof, and the individual contacts extend from the contact fingers.
 9. The switch of claim 8, wherein the first stamped inductance members are integral with a least a plurality of the contact fingers and project from the outer edge of the annular member, said inductance members being provided with a slot.
 10. The switch of claim 9, comprising a plurality of second stamped inductance members connecting the first stamped inductance members in series, each of the second stamped inductance members being provided with a slot and comprising a fan for altering the inductance thereof.
 11. In an electric switch, the combination of a first contact carrier of insulating material, a plurality of individual contacts fixed to the first contact carrier and projecting from a surface thereof, a common contact, supporting means integral with the common contact and fixed to said carrier mounting the common contact in spaced relationship to the individual contacts, a second contact carrier of insulating material in front of and movable relative to said surface of the first contact carrier, said bridging contactor comprising a first and second contact engaging portions, a base portion connecting the contact engaging portions together, one of the contact engaging portions having a predetermined transverse dimension, the longitudinal axis of the one contact engaging portion being spaced from the longitudinal axis of the other contact engaging portion at least twice predetermined dimension, the first contact engaging portion moving in a path having circuit making engagement with said common contact and the second contact engaging portion moving a in a path selectively engaging the individual contacts as the second contact carrier is actuated relative to the first contact carrier to selectively electrically connect the individual contacts with the common contact.
 12. The switch of claim 11, wherein the base portion connecting the contact engaging portions together spans a distance equal to the distance spanned by the plurality of individual contacts.
 13. The switch of claim 12, wherein the individual contacts and the common contact are spaced the same distance from the surface of the first contact carrier. 